1. Field of the Invention
The present invention relates to a print, a printing method, a printer, and an image reading method and device capable of inhibiting improper reproduction. More particularly, the present invention relates to a print, a printing method, a printer, and an image reading method and device in which indicia for security against reproduction can be recorded without lowering image quality.
2. Description Related to the Prior Art
As digital copying device have been developed today, it is possible to produce a duplicated material easily with very high precision in a form that human eyes cannot discern from an original image sheet. There have been dealers who produce and sell unauthorized copies by duplicating original image sheets. It is necessary to prevent the unwanted duplication.
U.S. Pat. No. 5,752,152 (corresponding to JP-A 09-226228) discloses a technique in which micro dots are formed in an original image sheet in a form invisible to human eyes, and duplication of the original image sheet is inhibited when a copying machine detects the micro dots. However, a duplicated material cannot be discerned from the original image sheet by human eyes. It is impossible to prevent illegal trade of the duplicated material.
WO 94/01288 (corresponding to JP-A 503899) discloses a protection sheet, which is attached to a print in such a manner that an image in the print can be viewed if inclined under daylight, but cannot be retrieved by a scanner or the like for reading in the vertical direction. With the protection sheet attached to the print, illegal duplication of the print is prevented even if no specialized copying machine is used. However, there is a problem in that the attachment of the protection sheet to the print lowers the quality of the print or definition of its image. Furthermore, an additional process of attaching the protection sheet is required. The print cannot be obtained easily in the form protected from duplication.
In view of the foregoing problems, an object of the present invention is to provide a print, a printing method, a printer, and an image reading method and device in which indicia for security against reproduction can be recorded without lowering image quality.
In order to achieve the above and other objects and advantages of this invention, a print is produced by image recording to thermosensitive recording material including a support and at least one thermosensitive coloring layer overlaid on the support. At least one colorless gloss indicia is recorded by thermal recording, and discernible according to a glossiness difference.
In a preferred embodiment, the recording material further includes a protective layer overlaid on the coloring layer. The gloss indicia is thermally recorded to the protective layer.
The recording material is color thermosensitive recording material, and the at least one coloring layer comprises first, second and third coloring layers, overlaid on the support in sequence on one another, colorable in predetermined colors.
The print comprises an effective printing region adapted to the image recording. A margin region is disposed outside the effective printing region. The gloss indicia is disposed in the margin region.
The print comprises an effective printing region adapted to the image recording. The gloss indicia is disposed in the effective printing region and close to an end thereof.
According to one aspect of the invention, a printer is provided for image recording to thermosensitive recording material including a support, at least one thermosensitive coloring layer overlaid on the support, and a protective layer overlaid on the coloring layer. A thermal head is provided for thermal recording to the coloring layer. A controller controls the thermal head, and thermally records at least one colorless gloss indicia by heating the protective layer at a predetermined temperature during or after the thermal recording to the coloring layer, the predetermined temperature being lower than a temperature at which the coloring layer is colored and higher than a glass transition point of the protective layer, the gloss indicia being discernible according to a glossiness difference.
The recording material is color thermosensitive recording material, the at least one coloring layer comprises first, second and third coloring layers, overlaid on the support in sequence on one another, colorable in predetermined colors, and the second and third coloring layers have fixability to electromagnetic rays. The thermal head effects the thermal recording to the third, second and first coloring layers in sequence. Furthermore, a fixer fixes the third coloring layer after the thermal recording to the third coloring layer and fixes the second coloring layer after the thermal recording to the second coloring layer by use of the electromagnetic rays. The predetermined temperature is lower than a temperature at which the first coloring layer is colored.
According to another aspect of the invention, an image reading device comprises an image reader for reading an image from an original. A glossmeter unit measures glossiness of respectively unit areas in the original. An arithmetic operation unit obtains an average glossiness of the glossiness of respectively the unit areas. An indicia discriminator checks existence of a gloss indicia according to a glossiness difference between the glossiness of respectively the unit areas and the average glossiness. A controller allows the image reader to operate if the gloss indicia lacks, and generates an alarm signal if the gloss indicia exists.
The alarm signal is adapted to disable the image reader from operating or from outputting data.
Furthermore, a moving mechanism moves one of the original and the glossmeter unit relative to a remaining one thereof in a sub scan direction. The glossmeter unit includes a light source for applying inspection light to the original. A glossiness sensor includes plural photo receptor elements arranged in at least one array in a main scan direction crosswise to the sub scan direction, for generating information of the glossiness of respectively the unit areas by detecting the inspection light reflected by the original.
The light source and the glossiness sensor are so disposed that the inspection light is incident upon the original at an incidence angle xcex81 and reflected by the original at a reflection angle xcex82, and satisfy a condition of:
xcex81=xcex82xe2x89xa660xc2x0.
The light source and the glossiness sensor are combined in a single unit.
The image reader reads the image in a line-shaped reading region extending in the main scan direction in the original. The moving mechanism further moves the image reader with the light source and the glossiness sensor.
According to still another aspect of the invention, a printer is provided. An image reader reads an image from an original to obtain image data. An image forming unit forms an image according to the image data. A glossmeter unit measures glossiness of respectively unit areas in the original. An arithmetic operation unit obtains an average glossiness of the glossiness of respectively the unit areas. An indicia discriminator checks existence of a gloss indicia according to a glossiness difference between the glossiness of respectively the unit areas and the average glossiness. A controller allows the image forming unit to operate if the gloss indicia lacks, and generates an alarm signal if the gloss indicia exists.
The alarm signal is adapted to disable the image reader and/or the image forming unit.
The glossmeter unit operates while or before the image reader operates.